Lenovo IdeaPad 100 board is dead

[coolerman]

hello guys!

received this motherboard model nm-a681 for change the jack dc port(change it all ok)after push side power button and is dead(no reaction/no spin fan) nothing is dead
with multimeter read to pq301 and pq302 have 20v both
can help me anyone;;?

[techtiger]

check the voltage of the first 2 Fets PQ301 PQ302 GATE SOURCE DRAIN after check the voltage of the CLR PR301 both side if you dont get +19V at the PR301 that means you 2 Fets Gate voltage is missing or one of the Fets short

[techtiger]

here is the Schematic check out the page 53

[coolerman]

Originally Posted by techtiger

check the voltage of the first 2 Fets PQ301 PQ302 GATE SOURCE DRAIN after check the voltage of the CLR PR301 both side if you dont get +19V at the PR301 that means you 2 Fets Gate voltage is missing or one of the Fets short

check with my polymeter(pq301 and pq 302) and to pr 301 has 20v(is correct voltage i think) both side.

[techtiger]

ok that's good let’s move no find out PJ303 PJ306 this are jumpers and there out put , PU200 is your 3V Regulater IC you need to find out out put voltage of pin 17 , Pu201 is your 5V Regulater IC find out out put voltage of pin 15, UE1 is the SUPER IO CHIP SIO page 44 find out the voltage on pin 71 128 110

[mcplslg123]

Check PQ303 located near battery connector. Often, this mb goes dead 'coz of shorted pq303. have found so on 3 occasions.

[coolerman]

pj303(0v) pj 306(0v)pu200 pin 17(don't have 3v)PU 201 pin 15(have it 5v) pin 128(super i/o 0v)pin 71(super i/o 0v)pin 110 (super i/o 0v)
check again but don't have mistake for my measurement.

[coolerman]

Originally Posted by mcplslg123

Check PQ303 located near battery connector. Often, this mb goes dead 'coz of shorted pq303. have found so on 3 occasions.

Check with polymeter and pq 303(pv507ba) has on side 20v the other side of pin is 0v

[techtiger]

Originally Posted by coolerman

pj303(0v) pj 306(0v)pu200 pin 17(don't have 3v)PU 201 pin 15(have it 5v) pin 128(super i/o 0v)pin 71(super i/o 0v)pin 110 (super i/o 0v)
check again but don't have mistake for my measurement.

No supply 0V means +19V is absent in +B change that Fet

[coolerman]

Originally Posted by techtiger

No supply 0V means +19V is absent in +B change that Fet

can tell me what is location(and change it this fet)for repair;
(sorry but i don't know very good english and i use it translate)

[techtiger]

You have to find out a P channel 6 legs forward base mosfet 30V from a spair motherboard

[coolerman]

Originally Posted by techtiger

You have to find out a P channel 6 legs forward base mosfet 30V from a spair motherboard

Ok
Hope solve my problem this fet.
Change it and see what happens.
Thanks

[mcplslg123]

Originally Posted by coolerman

Check with polymeter and pq 303(pv507ba) has on side 20v the other side of pin is 0v

I beleive that's fine. The otherside you are talking about is connected to battery and since battery is disconnected, you are not supposed to get any voltage there.

[techtiger]

yep that's correct I miss that it's +B between PR301 PL302 goes to 3/5 Regulator IC

[coolerman]

It's normal this fet (pq303;?)don't replace them.
Can check other place and find this problem caused;?

[techtiger]

You have to check PJ303 PJ305 getting +B 19V for those 2 jumpers

[coolerman]

.

[coolerman]

Originally Posted by techtiger

You have to check PJ303 PJ305 getting +B 19V for those 2 jumpers

hi gays again
check PJ303(don't have 20v) but to PJ305(have it 20v)

[mcplslg123]

PJ303 SHOULD BE 3V and not 20v. Similarly PJ306 should be 5V but i beleive these voltages will appear only after power on. If there is no shorting on those pads, problem may be elsewhere.

[coolerman]

pj 305 have it 5v, pj 303 don't have 3v the pu200(same area) coming 20v but is out pin 16 don't have 3v




and this litl capacitor i thing is short(biping mode)